| Titanium dioxide is a kind of important semiconductor photocatalysis material and it has many advantages, such as high activity, anti-photochemical and chemical erosion, well stability, correspondingly low price and intoxicity. Many organic molecules will be photo-degraded completely by photo-catalyst TiO2, so it has offered considerable potential for wide use in many fields such as prevention and cure to environment pollution, water treat with, air purifying, the preparation of self-cleansing materials. As more attention is paid to environmental protection, photocatalysis material TiO2 has been focus on material science and catalysisology. However, TiO2 is a wide band gap materials, narrower spectral response, the less efficient the use of solar energy, but also difficult to filter and recycling, to a large extent limited its practical application. In order to improve the practicality of TiO2, woke below was done in this paper:The techniques of transitional metal ions doping was designed in my research work. The synthesis methods of doped TiO2 were probed in the first instance. Taking simple and low-cost inorganic salts as raw materials, nanometer-sized TiO2 powdes modified with Ce doping were prepared by normal pressure hydrothermal method. XRD analysis showed that they had tetragonal anatase structure. The powders are less aggregation and symmetrically ball-like through TEM analysis and particle size is about 20 nm. The applying experiment testified that modified TiO2 had higher reaction activity and velocity and efficiency of degration towards organic dyes.Based on the development of the mesoporous materials, we not only improve catalyst's absorption capacity by virtue of high specific surface areas of materials, but also by way of the metal element doped TiO2 photovoltaic to impel the electronic and cavity separation, in order to enhance photocatalysis' efficiency and widen spectral response range of TiO2 from two aspects. So in this article, mesoporous materials TiO2 with Ce adulterated were prepared by hydrothermal method, through joining surfactant CTAB with PEG or emulsifier OP composite template. Meanwhile, the best crafts parameters were obtained through optimizing various factors influencing the reaction. The structure of the synthesized product was discussed by XRD analysis; proved that the products belong to the Department of tetragonal anatase structure. TEM observation of samples used for the disordered morphology of mesoporous materials, can clearly see that the vermiculate ostium. Products' N2 adsorption- desorption isotherms curve was the Langmuirâ…£shape type, was a typical mesoporous structure of the adsorption-desorption isotherm curve and calculated its size was between 10-20nm. Optical Absorption and Adsorption experiments show that:Hydrothermal Synthesis of Nano-CeO2-TiO2 composite mesoporous materials were superior in the adsorption properties than the non-synthesis with mesoporous products, and confirmed:Mesoporous materials in the UV and visible light district had higher light absorption performance than the non-mesoporous nano-TiO2 powder. Photocatalytic experiments showed that:the compositive Nano-CeO2-TiO2 composite mesoporous catalyst in this experiment in the sunlight in less than 40min to complete decolorization and degradation the organic dye can be close to 100%, compared with the non-mesoporous nano-TiO2 powder decolorization and degradation of the time by nearly half. On the powder proved recycling:the mesoporous powder filterd fast, high recovery, and reuse effect of the mesoporous powder was better than the non-mesoporous nano-TiO2 powder.
|
PDF Full Text Request